The Superfund program at University of California Davis has produced assays for many environmentally hazardous materials. The application of these bioassays in fast, multi-analyte instruments requires further work that will be undertaken in the Biosensor projects. Initially, engineering of surface microdot systems will be carried out for model assays for atrazine and metabolites. Small dots of antibodies will be printed onto a surface and then exposed to samples. The sensitivity of the surface microdot system will be explored on the model assay. Automation of steps in cell based assays will also be investigated. Novel fluorescence labels will be developed in collaboration with other projects in the program. Three classes of new labels will be tested; they include porphyrins and lanthanides that are amenable to time resolved fluorescence detection. Fluorescence resonance energy transfer (FRET) will be investigated as a promising label. Experiments will be carried out on simple solutions and on a model assay for atrazine to evaluate sensitivity and detection limits. Microdroplets will be investigated a novel format for fluorescence detection. Micron sized droplets of sample with be interrogated with a laser. The possibility of using non linear optical processes, such as droplet lasing, in the microdroplets will be determined. Microfabrication technology will be used to design and fabricate miniaturized systems for immunoassays. Sample handling and processing will be incorporated into the miniaturized device. Ultrasonic agitation will be investigated as a way to improve binding rates. Finally, the miniaturized immunoassay system will be interfaced with novel detection methods, using new fluorophores and new detection formats (such as microdroplets). The sensitivity, detection limits, and turn around time of the packaged system, will be evaluated on atrazine and other compounds of interest, including dioxin and human reproductive hormones.